Mechanical properties of hybrid multilayer graphene/whisker-reinforced ceramic composites: Simulation and experimental investigation.

The trial-and-error method used in ceramics research has certain limitations such as the high blindness of material component design. Moreover, calculations of the toughness of ceramics using the extended finite element method, which is the most broadly applied technique, are complicated. To overcome these issues, in this study, multilayer graphene (MLG)/Si 3 N 4 whisker (Si 3 N 4w)-reinforced Si 3 N 4 ceramics (MWSCs) were used as the model material, and the modeling of MWSCs was conducted using Voronoi tessellation. Additionally, a more concise novel approach was applied for the prediction of the fracture toughness of MWSCs. Furthermore, the optimal MLG and Si 3 N 4w contents were predicted, and then they were verified by fabricating MWSCs using spark plasma sintering (SPS). Simulation results indicated that the optimum MLG and Si 3 N 4w contents to enable the toughness and hardness to reach the maximum values (9.87 MPa·m1/2 and 23.19 GPa) were 1 wt% and 3 wt%, which were consistent with the experimental results. Consequently, the effectiveness of the proposed method was verified. Moreover, the experimental values of the maximum fracture toughness and hardness were 11.04 MPa·m1/2 and 20.29 GPa, which were 47.20% and 12.10% higher than those of Si 3 N 4 ceramics reinforced with 1 wt% MLG, respectively. The synergistic toughening effects of MLG and Si 3 N 4w were significantly reflected. The load-bearing effect, bridging, and crack deflection induced by MLG and Si 3 N 4w were the key reasons for the improvement in the mechanical properties of MWSCs. [ABSTRACT FROM AUTHOR]